Shallow-flow visualization analysis by proper orthogonal decomposition
Shallow-flow visualization analysis by proper orthogonal decomposition
复制标题
DOI：
10.1080/00221686.2011.585012
复制
发表时间：
2011-09
影响因子：
2.3
通讯作者：
W. Brevis;M. García-Villalba
中科院分区：
文献类型：
--
作者：
W. Brevis;M. García-Villalba
识别空间特性和脱落频率的相干结构在浅水流中通常涉及到使用先进的设备，如激光多普勒测速仪或粒子图像测速仪的速度测量。在这项工作中，一个简单的和低成本的替代准二维浅相干结构的定量表征。该技术是基于流动可视化的图像预处理和后处理的适当的正交分解。作为该方法的一个例子，本文给出了一个具有涡街模式的圆柱尾迹中的浅水流动的分析。该方法是能够区分浓度补丁附加到涡和他们的平流，提供与以前的研究非常一致的频率。
The identification of the spatial characteristics and the shedding frequencies of coherent structures in shallow flows usually involves the use of sophisticated equipment for velocity measurements such as laser Doppler anemometry or particle image velocimetry. In this work, a simple and low-cost alternative for the quantitative characterization of quasi two-dimensional shallow coherent structures is presented. The technique is based on the image pre-processing of flow visualizations and post-processing by means of the proper orthogonal decomposition. As an illustration of the method, the analysis of a shallow flow in the wake of a cylinder with a vortex-street pattern is presented. The method is able to discriminate concentration patches attached to the vortices and their advection, providing frequencies in excellent agreement with a previous study.